Assignment2-Report.md

Assignment-2

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1. Selected C syntax subset

   • variable declaration/variable initialization
     • int
     • float
     • char
   • simple statements
   • branches
     • if / if-else
       • supports binary operation as condition
     • loop
       • supports only while loop
   • functions
   • basic arithmetics
     • +, -, *, /

2. Defined tokens and output format

   • Defined tokens
     • %token <_symbol> ID
     • %token <_doubleVal> DOUBLE
     • %token <_intVal> INT
     • %token <_type> TYPE
     • %token <_string> STRING
     • %type <_doubleVal> stmt_list
     • %type <_doubleVal> stmt
     • %type <_doubleVal> element
     • %type <_doubleVal> term
     • %type <_doubleVal> factor
     • %type <_doubleVal> declaration
     • %type <_doubleVal> arg_list
     • %type <_doubleVal> arg
     • %type <_type> branch_list
     • %type <_type> branch_condition
     • %type <_type> func_args
     • %token IF WHILE FOR
     • %left <_intVal> GT
     • %left <_intVal> LT
     • %left <_intVal> GEQ
     • %left <_intVal> LEQ
     • %left <_intVal> EQ
     • %left <_intVal> NEQ
     • %left <_intVal> OR
     • %left <_intVal> AND
     • %nonassoc IFX
     • %nonassoc ELSE
   • Output format
     • this parser follows the output format shown on the p.41 of the assignment explanation slides. The Lex part will also check if a symbol exists or not and perform the corresponding actions such as insert a new key into the symbol table.

3. Implementation obstacles

   • This assignment is much harder than the previous one. It takes me for about few weeks to finish it.
   • Designing a proper grammar is a challenging task for me, which is also the main task of this assignment.
   • The co-working between YACC and LEX also took me a lot of time.

4. Known Bugs

   • Does NOT support for loop.
     • the condition part of for loop is way complicated than I've ever imagined, so I gave up eventually.

5. Anything worth to be mentioned

   • I'm still thinking...XD